The present invention relates to a nutritional method for reducing the incidence of frequently encountered health problems in periparturient cows and, more specifically, to an improved method for calcium administration in dairy cows.
Parturition and the onset of lactation impose severe physiological stresses on the dairy cow. It has long been recognized that severe hypocalcemia or low blood calcium, which is a common condition of periparturient cows, is a direct cause of milk fever. Also, calcium is very important for muscle contraction and is essential for normal uterine contractions in expelling the placenta.
Intravenous injections of a calcium solution have been used as a treatment for milk fever, after the onset thereof. However, a relatively high time and cost are involved in intravenous administration, as well as creating a new danger of death from the rapid increase thus produced in the blood calcium level. The practice of injecting calcium intravenously as a cure for milk fever is discussed in Yearbook of Agriculture "Keeping Livestock Healthy" U.S. Department of Agriculture, 1942, at page 584. The 1956 edition of the same publication, at page 244, also recognizes the calcium adminstration may be beneficial for cows that have had milk fever, but does not suggest the level of dosage, manner of administration, etc., and concludes that none of the previously attempted methods of preventing milk fever has had much success.
Among the various methods which have been suggested for maintaining or restoring blood-calcium levels to combat milk fever or other calving-related health disorders are those which involve prolonged dietary programs. That is, cows are given special supplements along with their usual rations over a prolonged period which may extend both before and after parturition. An example of this type of this type of dietary plan is that described in British Pat. No. 1,542,838. This method involves maintaining the available calcium intake of the cow at about 30 grams per day for a period of at least 4 to 5 weeks until at least one day prior to parturition, at which time the intake is increased to a level of 50 to 130 grams. Since the exact time of parturition is difficult to judge in advance, this method is subject to errors in estimating the future time of parturition. Furthermore, the method requires special delivery supervision and control over each cow in a herd in accordance with projected calving dates during a period of many weeks which is obviously a tedious and time consuming task, subject to further errors.
A principal object of the present invention is to provide improved methods of establishing blood calcium levels in periparturient dairy cows which significantly reduce health problems connected with hypocalcemia prior to the onset thereof.
Another object is to provide preventive methods of the aforementioned type which are fast, efficacious and easy to administer.
A further object is to provide methods of controlling health disorders prior to the onset thereof in periparturient dairy cows which employ inexpensive and readily accessible materials.
Still another object is to provide a method for significantly reducing the incidence of calving-related health disorders in dairy cows which does not involve estimation of future parturition dates while insuring that each cow receives the necessary dosage in a single step.
Other objects will in part be obvious and will in part appear hereinafter.